Turkish-backed rebels and Kurds battle over Syria's al Bab

Syrian rebels backed by Turkey who are trying to drive Islamic State (ISIS) from the city of al Bab said on Monday they clashed with U.S.-backed Kurdish forces as both groups seek to dislodge the militants to expand their own territory.

The rebels said the fighting with the Syria Democratic Forces (SDF), a coalition of Kurdish and Arab tribal fighters, led by the Syrian Kurdish militia YPG, erupted in the village of Sheikh Nasser.

The village and others that were captured by the Turkish- backed operation were until recently in the hands of Islamic State and part of the militants' last enclave near the Syrian-Turkish border. "We clashed with the Kurdish YPG and we took over the village," said Abu Assad Dabeq, a commander in the Turkish-backed Operation Euphrates Shield. The operation was launched in August when Ankara sent warplanes, tanks and artillery into Syria in support of mostly Arab and Turkmen rebels.

The SDF could not be immediately reached for comment and there was no way of independently verifying if the rebels did have control of the village. Turkish President Recep Tayyip Erdogan has said seizing control of al Bab, around 30 km south of the border, is a goal of the operation before targeting Manbij, where Kurdish-led forces drove out Islamic State, and the militants' de facto Syrian capital of Raqqa.

Ankara views the YPG militia as a hostile force with deep links to Kurdish militants who have fought a three-decade insurgency on Turkish soil. Ankara has also said YPG fighters should not be involved in the planned Raqqa offensive. So far, the rival sides have had minimal direct confrontation as they compete to grab territory from the retreating Islamic State who once dominated swathes of territory from the Turkish border further south towards Aleppo city.

"The YPG are trying to advance to the areas we are advancing to," said Abu Assad Dabeq, adding his troops were already only a few kilometres away from al Bab and were fortifying their positions to hold back any advance by Kurdish-led forces. "They are competing with us to reach al Bab. They are working on cutting all roads either from Aleppo or in the direction of al Bab," he added.

The SDF had effectively created a belt that separated the mainly Arab Sunni rebels from where the Syrian army was positioned further south, he added. Capturing al Bab would be a significant victory for Ankara, which is seeking to establish a de facto safe zone and thwart Kurdish hopes of establishing a corridor between areas east and west of the Euphrates.

The Syrian army is also nearly 12 km south of the city. Damascus has said it would not allow Turkey's allies to take the city. A fighter in Failaq al Sham said the Turkish army had since Saturday stepped up its artillery shelling and aerial raids of both the militants in Qabasin, located on a strategic ground that overlooks al Bab, and the SDF in their newly gained villages in an attempt to halt their advance.

"The Turkish air force is helping to push back the YPG militias who have been exploiting our gains from Islamic State to step into villages vacated by the militants," Abu Anas said referring to four villages west of Manbij that SDF-affiliated forces captured, including the contested Sheikh Nasser.